Means for unblocking pipes



Sept. 12, 1961 D. J. STEARNS MEANS FOR UNBLOCKING PIPES Filed April 4,1960 INVENTOR.

DONALD J. STE ARNS United States Patent 2,999,264 MEANS FOR UNBLOCKINGPIPES Donald J. Stearns, 33 E. I St., Chula Vista, Calif. Filed Apr. 4,1960, Ser. No. 19,875 Claims. (Cl. 15406) The present invention relatesgenerally to plumbing equipment and more particularly to means forunblocking pipes.

The primary object of this invention is to provide means for unblockingpipes, drains and the like utilizing compressed gas discharged from apressurized can held in a frame and having pipe sealing means whichenables the full effect of the gas to be utilized without leakage.

Another object of this invention is to provide pipe clearing means inwhich the pressurized can is a replaceable, sealed unit, the gas beingreleased by puncturing the can with a bayonet type piercing meansintegral with the gas outlet pipe.

Another object of this invention is to provide pipe clearing means inwhich the pressurized can is held safely clear of the piercing meansuntil intentionally pierced by forcing the device firmly against thepipe to be cleared, the handle of the device incorporating a pre-loadingspring which holds the can securely to prevent blow-back.

A further object of this invention is to provide pipe clearing meanswhich may be used with many difierent sizes of pipes, drains or in sinksor toilet bowls, the sealing means being adapted to fit closely into theopening or end of the pipe.

Finally, it is an object to provide pipe clearing means of theaforementioned character which is simple, safe and convenient to use andwhich will give generally efiicient and durable service.

With these and other objects definitely in view, this invention consistsin the novel construction, combination and arrangement of elements andportions, as will be hereinafter fully described in the specification,particularly pointed out in the claims, and illustrated in the drawingwhich forms a material part of this disclosure, and in which:

FIGURE 1 is a side elevation view of the complete structure;

FIGURE 2 is a sectional view taken on the line 22 of FIGURE 1; and

FIGURE 3 is a sectional view taken on the line 3--3 of FIGURE 2.

Similar characters of reference indicate similar or identical elementsand portions throughout the specification and throughout the views ofthe drawing.

The structure includes an open frame having a pair of side bars 12 ofmetal rod or the like, said side bars being inwardly bent and connectedto a base collar 14 at one end and fixed to a guide collar 16 at theother end thereof, the two collars being coaxial. The base collar 14 hasa concentric inner hub 18 in which is fixed a tubular spout 20 having adownwardly extending nozzle 22, said spout also extending upwardly andhaving a pointed end or bayonet portion 24. Slidably mounted on thespout 20 is a barrel 26 with an enlarged upper cup portion 28, the lowerend of said barrel having an outwardly extending flange 30 which restson a safety spring 32 seated in the base collar 14. The slidingconnection between the spout 20 and barrel 26 is preferably made leakproof by a suitable sealing ring 33. The upper end of the cup portionhas an annular rim 34 holding an O-ring 36, which is normally held abovethe bayonet portion 24 by the safety spring 32.

Fixed to the nozzle 22 is sealing plug 38 having a radially extending,generally conical skirt 40, of resilient material such as rubber or thelike. The skirt engages the edge of an opening or pipe, as indicated at42 in FIGURE 2, and seals the opening when the plug 38 is insertedtherein. 1

Slidably mounted in the guide collar 16 is a plunger assembly comprisingan outer sleeve 44 at the lower end of which is fixed a generallycircular pressure pad 46, the upper end of said outer sleeve having anoutwardly projecting stop 48 to limit downward travel thereof. Fittedslidably in the outer sleeve 44 is an inner sleeve 5% carrying at itsupper end a bar type handle 52 for holding the tool. The inner sleeve 5%is supported on a preload spring 54 fitted therein between the pressurepad 46 and handle 52, but is held against displacement by a link chain56 connecting said handle to a lug 58' on said pressure pad. A cord orwire may be used in place of the link chain 56 if desired, the onlypurpose being to prevent separation of the various parts.

The pressurized gas is provided in a rupturable, nonshattering container60 which will ordinarily be a can with a dished end 62, the pressure pad46 being shaped to fit said dished end and conveniently hold the can.The other end of the can 60 has a reduced neck 64 which seats seourelyon the O-ring 36, said neck having an end cap 66. The precise structureof the container or can 60 is immaterial since such cans are readilyavailable and construction varies. The gas to be contained in the can isalso variable and can be air, carbon dioxide, or the like. Oneparticularly suitable gas, however, is freon and, when used, may becombined with a quantity of 'water in the can. Since freon is readilysoluble, the release of pressure when the can is punctured is prolongedslightly, rather than having a somewhat explosive effect. The prolongedpressure may be more. desirable where the piping to be unblockedcontains slip joints or other connections which might be displaced by asudden explosive pressure.

In use the can 60 is loaded in place and held between the cup portion 28and pressure pad 46, while the sealing plug 38 is applied to the openingor pipe to be cleared.

Initial pressure on the handle 52 telescopes the inner sleeve 50 intothe outer sleeve 44 and compresses the preload spring 54, clamping thecan 60 tightly and forcing the sealing plug skirt 40 into firm sealedcontact with the opening or pipe. Continued pressure on the handle 52overcomes the resistance of the end cap 66 to rupture by the bayonetportion 24 coupled with the resistance of the safety spring 32 andforces the can 60 downwardly, as indicated in broken line in FIGURE 2,causing the bayonet portion 24 to pierce the end cap 66 and release thecompressed gas through the nozzle 22. Once the bayonet point 24 rupturesthe container 60, the weaker safety spring 32 is completely overcome andthe compressed overload spring 54 quickly expands to supplement themanual downward force applied on the handle 52. In actual practice theoperation is accomplished by a single firm thrust. The pressure of thepreload spring 54 prevents any blow-back or leakage from the cup portion23, the can being securely held between two spring biased supports whichabsorb any sudden motion of the can at the instant of pressure release.

By using a self-contained pressurized can which is discarded after use,pressure reservoirs and their associated valving are eliminated,together with the problem of recharging. The cans may be made and filledrelatively cheaply, so that the cost per operation may be less than thecost of labor involved in using a snake or other mechanical device toclear pipes. An advantage of the addition of a small quantity of waterin the can 60 should be noted, since it enables the employedment of astandard sized container to provide for a whole range of maximumpressures and a corresponding range in thrust duration, merely byvariation of the amount of water in the container.

The operation of this invention will be clearly comprehended from aconsideration of the foregoing description ofthe mechanical detailsthereof, taken in connection with the drawing and the above recitedobjects. It will be obvious that all said objects are amply achieved bythis invention.

It is understood that minor variation from the form of the inventiondisclosed herein may be made without departure from the spirit and scopeof the invention, and that the specification and drawing are to beconsidered as merely illustrative rather than limiting.

I claim:

1. Means for unblocking pipes, comprising: a rigid frame having a gasconducting spout at one end thereof and a pipe-engaging sealing memberon said spout; a cup member axially slidably mounted on said spout; amanually operable plunger assembly mounted at the other end of saidframe for sliding movement coaxially of said cup member; a rupturable,non-shattering container of pressurized gas; said plunger assemblyhaving a pressure pad resiliently biased to engage said container andhold the same between said pressure pad and said cup member; said spouthaving a bayonet point adjacent to said cup and extending toward saidplunger assembly to pierce said container when said plunger assembly ismoved toward said bayonet point.

2. Means for unblocking pipes, comprising: a rigid frame having a basecollar at one end; a guide collar at the other end of said frame coaxialwith said base collar; a gas conducting spout fixed in said base collarand having a substantially resilient, pipe-engaging sealing plug fixedthereto outwardly of said frame; said spout having a bayonet portion atthe end thereof disposed inwardly of said frame; a cup member slidablymounted on said spout; a rupturable, non-shattering container ofpressurized gas having a neck end adapted to seat in said cup member insealed relation therewith; a plunger assembly axially slidably mountedin said guide sleeve and engaging the other end of said container tohold the same in place; and a safety spring between said base collar andsaid cup member to hold said container clear of said bayonet portion.

3. Means for unblocking pipes, comprising: a rigid frame having a basecollar at one end; a guide collar at the other end of said frame coaxialwith said base collar; a gas conducting spout fixed in said base collarand having a substantially resilient, pipe-engaging sealing plug fixedthereto outwardly of said frame; said spout having a bayonet portion atthe end thereof disposed inwardly of said frame; a cup member slidablymounted on said spout; a rupturable, non-shattering container ofpressurized gas having a neck end adapted to seat in said cup member insealed relation therewith; a plunger assembly axially slidably mountedin said guide sleeve and engaging the other end of said container tohold the same in place; said plunger assembly including telescopicallyslidable sleeve elements having a preload spring therebetween biasingthe elementsapart; a pressure pad on one of said sleeve elementsengageable with said container; a handle fixed to the other of saidsleeve elements for manual compression of said preload spring; and asafety spring between said base collar and said cup member to hold saidcontainer clear of said bayonet portion.

4. Means according. to claim 3 wherein said container is charged withfreon gas and a small quantity of water. 5. Means according to claim 3wherein said preload spring is stronger than said safety spring.

References Cited in the file of this patent UNITED STATES PATENTS2,300,319 Smith Oct. 27, 1942 2,601,211 Neely June 17, 1952 2,725,048Koogle Nov. 29, 1955 FOREIGN PATENTS 2,516 Great Britain Feb. 20, 1886

